Steam trap



Feb. 2 1926. 1,571,921

F. L. HUTCHINSON STEAM TRAP Filed May 51 1924 INVENTOR.

ATTORNEKS,

Patented Feb. 2, 1926. j 1

UNITED STATES PATENT OflFiFlQE.

FRANK L. HUTCHINSOIN, OF WAUWATOSA, WISCONSIN, ASSIGNOR, BY MESNE ASSIGNMENTS, TO MILWAUKEE VALVE COMPANY, OF MILWAUKEE, WISCONSIN,

A CORPORATION OF WISCONSIN.

STEAM TRAP.

' Application filed May 31, 1924. .Serial No. 716,980. i

To all whom it may concern: 7

Be it known that I, FRANK L. I-Inronnisort, a citizen of the UnitedStates, and resident of Wauwatosa, in the county of Milwaukee and Stateof Visconsin, have invented new and useful Improvements in Steam Traps,of which the following is a description, reference being had to theaccompanying drawings, which are a part of this specification. I a iThis invention relates to improvements in steam traps, and moreparticularly to a steam trap adapted to be connected to the return pipein a high pressure vapor or steam heating system.

In heating systems employed inbuildings, where steam under pressure isemployed, it is customary to control the admission of steam to theradiator and toprovide an outlet pipe to return water of condensationback to the boiler. In order to make the system conducive of the bestresults and to provide forlits maximum efficiency, it is necessary toprevent the passage of any of the live steam back through the returnpipe with the water of condensation. It is also necessary in systems ofthis character to provide means whereby air which may be trapped in theradiator can escape, so that the air will not act to prevent'theentrance of steam into the'radiator.

IVith the above in mind, therefore, it is one of the objects of thepresent invention to provide a device adapted to be connected to thereturn pipe and constructed to permit the passage of water ofcondensation therethrough and also any air trapped in a radiator, but atthe same time preventing the escape of live steam. V

A further object of the invention is to provide a device of the classdescribed particularly adapted for high pressure vapor and steam heatingsystems and arranged so that the value is controlled by a compoundleverage thereby obviating any sticking of the valve and insuringaneiiicient device.

A further object of the invention is to provide a steam trap which is ofvery simple construction, is strong and durable, and is well adapted forthe purpose described.

Vith the above and other objects in view,

the invention consists of the improved steam trap and its parts andcombinations asset forth in the claims, and all equivalents thereof. Inthe accompanying drawing in which the same reference characters indicatethe same parts in all of the views:

Fig. 1 is 'a front view of the improved steamtra'p, parts being brokenaway and shown in section;

Fig. 2 is an enlarged detail view showing the valve stem, the compoundleverage forv moving the same and the thermostatically controlled valve;and

Fig. 3 is an enlarged detail view of th thermostatically controlledvalve.

Referring now more particularly to the drawing it will be seen that thesteam trap consists of a casing 8, provided with airinlet opening 9 andan outlet opening 10. The casing is formed immediately adjacent theinlet opening with av chamber 11. in which is seateda screen or basket12 formed with perforated walls. Said member 12 serves to screen thewater of condensation entering the casing through the opening 9 andcollects sediment. The chamber 11 is provided with a cleaning opening 18closed by a threaded plug 14 and when desired said plug can be removedand the basket 12 grasped by its handle 15 and lifted from the chamberto permit emptying and cleaning of the basket. An'opening 16 formed inthe wall of the chamber 11 provides con'imunication between said chamberand the float chamber 17 of the steam trap. The upper side of the casingis open but is normally closed by means of a cover 18 removably held inplace by bolt and nut means 19 and 20, a washer member or gasket 21being interposed between the cover and the casing to prevent leakage.

Threaded in the bottom of the casing is a bushing 22 having formedtherein a valve seat, adapted to receive a valve 23 carried by a hollowtubular valve stem 24. The valve 23 and stem 24 are mounted for reciprocal movement in a guide member 25 Fixed to the valve stem 2% is acollar 27 v which has pivoted to opposite sides thereof, the endportions of a. pair of bell cranlc levers 28. The midportions oli saidhellcrank levers are pivoted to a depending arm 29, formed from theguide member A second pair of hell-crank levers 30 are pivoted at theirouter end portions to said depending arm 29, as at 31, and at their midportions to the lower end portions oi? the lirst mentioned belheranl;levers 28, as at 32. A hollow float 25? is carrir-al by the other endsof said bell-crank levers 3 Oln'iousl v, therefore, as the Heat israised, the valve stem 2% and the valve 23 will consequently be movedupwardly to unseat the valve. The compound leverag re provided by thearrangement just described renders the operation of the valve positiveunder all conditions. A considerable lllOVCll'lGni) ot the float resultsin but a small movement of the valve stem but the leverage arrangementresults in great force being applied to the sten'i in 'aisiiig' orlowering the same. Consequently, any tendency the valve may have tostick, will be easily overcome. Thus, the device is well suited for highpressure tems where pressure might cause the valve to becomeinoperative.

Fixed to the upper end ol the tubular valve stem 53-11 is a collar 23%having; secured thereto one end portion of a U-shaped, bimetalthermostat 3.7, Formed preferably ol. an outer strip of brass or copperand an inner strip of steel or other similar metal, having a ditllerentco-etlicient oit' expansitm. The collar 3% has an angular-iv shaped bore36 communicating with the valve stem opening and a valve 37, carried bythe end of the thermostat 35 is adapted in its (closed position to coverthe open end of the bore 36, thus closingcommunication through thehollow valve stem between the chamber 1i and the outlet 10.

It should be observed that the casing 8 is formed with a lower j arlvietportion 38 providing; an outlet; chan'iber 3E). The valve opening in thebushing opens thereinto and fluid is :lree to flow from said outletchamber through the outlet opening it). in the wall of the casingadjacent the bushing 22 a similar bushing -10 is located, the samebeing: formed with a valve seat to receive a valve -il-l. Said *alve llis moved inwardly and outwardly by means ol a hand wheel all? and servesas an auxiliary valve so that water mav be drained from the chamber i"?when desired. independently oi? the operation of the valve 23.

In operation the valve Q-i will normally re main in closed position, asshown in Fig. 1, while the thermostatic valve 3T remains in openposition. Conseipientl an v air tlowing into the chamber 1?, through theinlet opening 9. is free to pass from the chamber 1T through the tubularvalve stem 2% and down\vardlv throluzjh the chamber 39 and the outlet:opening; ll). its soon as any steam enters the chamber 1.? the heatthereof will cause an unequal expansion of the hi-metal parts of thethermostat 3:) and thus cause the valve 37 to seat against the open endof he bore 36 to close the same and the live steam will be confinedwithin the rzuliator.

The water at oiulensatum which llows into the chamber 17 will. m'aduallyaccumulate until it reaches height sullicient to actuate the Heat 33,which as it rises, will move the val e stem 24; and the valve 23upwardly to permit an escape of the water into the rhan'iber 39 and outtin-laugh the outlet openla 10. As the level oi the water decreases, thelloat will again drop and move the valve to the closed position. 1 hen asu'llicient quantity of water has again accumulated in the chamber 17,the cycle will be repeated.

Obviously, as the water of condensation passes into the chamber 11, anyforeign inatler onitained therein will be caught by and held in thebasket member 12, which can be pcriialically removed through the openingl3 and cleaned out. Access into the interior of the steam trap andchamber 1'? may be conveniently had by removing the cover 18, and shouldit become necessary to replace an portion of the operating partsillustrated in Figs. 52 and fl, this n'iay be accomplishcd by detaching;the guide member 25 from the projections 22o, whereupon all oi theseparts may be reunited as a unit from the interior of the valve. Thisfacilitates, to a considerable degree, the repairing or replacing, ofparts.

It is evident that the compound leverage arraiugenuml. between the valveand the float is construclol to exert great power in lifting the hive,thereby overcoming any tendency the valve may have to stick and alsopressure thereon, making the device well suited for high pressure stems.Also the improved steam trap ol very simple and novel crmslriurtion; andis well adapted for the purpose set forth.

lrhat I claim as my invention is:

1. steam trap, comprn no; a casing lei-hung a chamber provided. withinlet and outlet openings, a float, a :va ve provided with a valve stemtor controlling said out let opening. the stem oli said valve having apassage providing communication between said chamber and outlet o'iening, means for closing said passage, and a compound leverage betweensaid lioat and the valve stem for operating the valve.

:3. A steam trap, eonunising a casing 'l'ormiug a chamber provided withinlet and outlet openings, a Heat, a valve provided with a valve stemfor controlling said outlet opening. the stem oil said valve having 11pasi-"aapge providing;- communication between said chamber and outletopening, a U-shaped thermal member for closing said passage, and acompound leverage between said float and the valve stem for operatingthe valve. 8. A steam trap, comprising. a casing forming a chamberprovided with inlet and outlet openings, a float, a valve provided witha valve stem for controlling said outlet opening, the stem of'said valvehaving a passage providing communication between said chamber and outletopening, heat controlled means for closing said passage, and a compoundleverage between said float and the valve stem for operating the valve.

4. A steam trap, comprising a float chamher provided with inlet andoutlet openings, 1

ically actuated valve mounted on the end of 20 said stem for controllingsaid passage, and a compound leverage between said float and the valvestem for operating said first mentioned valve.

In testimony whereof, I aflix my signa- 25 ture.

FRANK L. HUTCHINSON.

